SPARK PLUG CHECK
Spark plug (2) gap shall be 0.028 ÷ 0.031 in.
A wider gap may cause difficulties in starting the
engine and overload the coil.
A gap that is too narrow may cause difficulties
when accelerating, when idling or poor performance
at low speed.
Clean the scale away from the base of the spark
plug before removing it from the cylinder, after re-
moving the cap (1).
It is very useful to examine the state of the spark
plug just after it has been removed from the engine
since the scale deposits on the plug and the colour
of the insulator provide useful indications.
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EN - 26
Correct heat rating:
The tip of the insulator should be dry and the colour
should be light brown or grey.
High heat rating:
In this case, the insulator tip is dry and covered with
dark deposits.
Low heat rating:
In this case, the spark plug has overheated and in-
sulator tip is vitrified (glazed), white or grey in col-
our.
CAUTION*: Carefully change the spark plug, if
necessary, using one having the same rating.
Before refitting the plug, thoroughly clean the
electrodes and the insulator using a metal
brush. Smear some graphite grease on spark
plug thread, do it fully home finger tight then
tighten it to 7.37÷8.85 ft-lb. torque. Loosen the
spark plug then tighten it again to 7.37÷8.85
ft-lb.
Spark plugs which have cracked insulators or
corroded electrodes should be replaced.
2
0,7 ÷ 0,8 mm
VOLTAGE REGULATOR
The voltage regulator (3) is fastened on the right-
hand side of the rear chassis.
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